This invention relates to notched V-belting which is mold formed, and the open-ended mold curing system associated therewith for the production of both single and multi-strand belts.
Joined multi-strand banded or bandless power transmission belting and drive systems therefore, are known, as shown for instance in U.S. Pat. No. 3,404,577 to Zahn. It is also known to provide these belts with notches in their undercord (compression section) as shown for instance in U.S. Pat. No. 4,011,766 to Waugh. Cure systems for these multi-strand joined belts, or for single strand belts using open-ended presses in which sections of the belt are consecutively cured in a stepwise manner are also known. Entire slabs or sleeves of belting, from which individual belts may later be obtained by cutting and profiling, or grinding, have also been produced stepwise in an open-ended curing process, employing in some cases rigid transversely notched mold extensions to facilitate indexing and alignment of the slab notches.
It is an object of this invention to produce a notched single or multi-strand V-belt whose notches are fully formed in a multi-cavity open-ended mold. It is a further object to produce a single or multi-strand V-belt with a fabric layer provided along the outer surface of undulating molded notches, such that the fabric retards initiation and propagation of cracks while serving to allow the unimpeded compression of the sidewalls of the belts in use, without substantial flexing of the fabric along the edges of the belt where compression is greatest. It is a further object that such fabric promotes release of the belt product from the mold. It is a further object to provide a joined multi-stranded belt having generally sinusoidal shaped notches in the compression section of the belt, which have been mold formed stepwise by a correspondingly shaped rigid mold portion.